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1.
厄尔尼诺是发生在热带中东太平洋海温异常增暖的气候现象,它是月到年际尺度全球气候变化中最重要和最强的信号.厄尔尼诺虽然发生在热带太平洋地区,但其影响却波及全球,对全球气候的短期变化有重要影响,造成世界上许多地区发生严重的旱涝和高低温灾害.2014年初,热带太平洋明显出现了厄尔尼诺事件爆发的一些前期物理信号,这些大气和海洋中呈现的前兆信号与爆发超级厄尔尼诺事件的1997年同期非常相似.本文利用卫星观测的高度计资料,精确地估计了表征次表层暖水东传过程的赤道开尔文波的变化.结果表明,相比自有1993年海表高度计卫星观测以来的6次厄尔尼诺事件,2014年3月赤道太平洋的开尔文波的向东传播速度是同期最快的,甚至明显地超过了1997年的超级厄尔尼诺事件.这些特征集中表明,2014年初的次表层暖水快速东传的现象,使得热带中东太平洋海表温度在未来几个月明显增暖,促使2014年爆发一次厄尔尼诺事件.  相似文献   

2.
首先,介绍了地球自转减速的研究现状,其次,利用粘性流体力学研究了地球大气粘滞性对地球自转减速的影响.根据被粘滞性大气包围的地球的自转能和角动量变化的2种理论推出了地球自转角速随时间减速的规律的同一式.利用所推出的理论式计算了在百年后地球自转角速的减少值.理论和计算结果表明:地球大气粘滞性对地球自转确实有减速的作用,但这种影响作用也确实很小,只能在长久岁月中(数千年以上)才能观测到.  相似文献   

3.
针对干旱预测的难题,利用揭示大气热结构垂直特征的V-3θ图,分析影响旱区的气流特征。根据国际地球自转服务(IERS)的数据,分析地球极移、章动和转速的变化与大气热结构变化的关系,基于地气动量守恒原理,将大气热结构与地球转动特征变化进行了制约性分析。结果表明,大气热结构异常和地球转动特征引起的冷空气路径变化与大范围干旱有关。  相似文献   

4.
利用黄、东海沿岸8个长期水文观测站多年海表温度资料,分析黄、东海沿岸海表温度的季节和年际变化特征,重点分析在1982-1983年和1997-1998年两次厄尔尼诺年期间的异常变化,以及ENSO影响黄、东海沿岸海表温度的可能机制.结果表明,在厄尔尼诺发生年,夏季风较弱,鄂霍次克海高压加强,西太平洋副高位置偏南,强度偏强,江淮流域及长江中下游降水偏多,黄、东海沿岸海表温度偏低.黄、东海沿岸海表温度受到ENSO和PDO(太平洋年代际振荡)的影响和调制,在厄尔尼诺发生的前冬半年及当年,黄、东海沿岸海表温度偏低;在厄尔尼诺发生次年,黄、东海沿岸海表温度偏高.厄尔尼诺对黄、东海沿岸海表温度变化的影响通过海洋和大气2个通道,1982-1983年海表温度异常以负异常为主,1997-1998年海表温度异常以正异常为主;ENSO期间,北赤道流减弱,黑潮流量减少,海表温度降低.海表温度受局地气温影响显著,如果ENSO期间东亚气温升高,则黄、东海沿岸海表温度偏高.  相似文献   

5.
地球自转不稳定性主要表现在白昼长度变化、地极移动、地球自转轴的旋进与章动等,其特征时间从几个小时到上千年不等。地球自转不稳定性和很多地球物理过程相关,如陆地上、海洋上、大气中的重力场和热力潮;大气圈和水圈的重分配;大气和海洋角动量的变化;大气、海洋和土地相互作用等。  相似文献   

6.
黄、东海沿岸海表温度变化与厄尔尼诺的关系   总被引:1,自引:0,他引:1  
利用黄、东海沿岸8个长期水文观测站多年海表温度资料,分析黄、东海沿岸海表温度的季节和年际变化特征,重点分析在1982—1983年和1997—1998年两次厄尔尼诺年期间的异常变化,以及ENSO影响黄、东海沿岸海表温度的可能机制。结果表明,在厄尔尼诺发生年,夏季风较弱,鄂霍次克海高压加强,西太平洋副高位置偏南,强度偏强,江淮流域及长江中下游降水偏多,黄、东海沿岸海表温度偏低。黄、东海沿岸海表温度受到ENSO和PDO(太平洋年代际振荡)的影响和调制,在厄尔尼诺发生的前冬半年及当年,黄、东海沿岸海表温度偏低;在厄尔尼诺发生次年,黄、东海沿岸海表温度偏高。厄尔尼诺对黄、东海沿岸海表温度变化的影响通过海洋和大气2个通道,1982—1983年海表温度异常以负异常为主,1997—1998年海表温度异常以正异常为主;ENSO期间,北赤道流减弱,黑潮流量减少,海表温度降低。海表温度受局地气温影响显著,如果ENSO期间东亚气温升高,则黄、东海沿岸海表温度偏高。  相似文献   

7.
根据地球自转变慢的事实解答了地磁能源以及地磁形成和倒向机制等当代地磁起源中突出的疑难问题.  相似文献   

8.
为了研究厄尔尼诺和南方涛动(ENSO)现象影响热带大气季节内振荡(ISO)的年代际变化特征,利用奇异值分解(SVD)、小波分析和经验正交函数分析(EOF)等方法对热带大气ISO强度指数、赤道中东太平洋海温及热带大气环流场进行了分析。计算结果显示,20世纪70年代中期以前,ENSO对热带大气ISO的影响较弱;70年代中期以后,ENSO对热带大气ISO的影响加强。造成上述年代际变化的原因与热带大气环流的年代际变化有关,因此,ENSO对热带大气ISO的影响也存在年代际变化。  相似文献   

9.
为使世界时间同地球自转的实际时间同步,2005年12月31日上午8时59分59秒时需增加一闰秒。那么,闰秒是怎么回事呢?天文气象学家解释说,给世界时间增加一秒钟是由于地球围绕太阳的公转和围绕自己轴心的自转速度变慢的  相似文献   

10.
回顾热带太平洋对海平面长期趋势有重要影响的海平面年际和年代际变化的相关研究,总结包括近期提出的中部型厄尔尼诺在内的2种类型厄尔尼诺对热带太平洋海平面年际变化的影响,揭示了热带太平洋海平面年代际变化与信风年代际变化之间的紧密联系。指出赤道信风的增强对近期热带太平洋海平面变化格局的形成有决定性作用,厄尔尼诺强度的减弱对这种格局有贡献,而拉尼娜的影响有待深入研究。研究资料的局限性导致年代际变化的定量研究成果较少,在研究海平面年际和年代际变化时应用的热通量评估模型有待改进。  相似文献   

11.
The relationship between the inter-annual variations of the earth rotation, atmospheric angular momentum (AAM), sunspot number and El Nifio is analyzed.The result shows that the inter-annual variation of the earth rotation responds to the variation of AAM and the pregnancy of El Nino timely. Generally, the inter-annual compohent of the earth rotation will reach zero in a changing process that increases from the negative to the positive extreme before El Nino occurs about half year or more. And the solar activity may have certain influence on the appearance of El Nino. We consider that El Nino will possibly appear around the end of 2001.``  相似文献   

12.
Three variation indices are defined to objectively and quantitatively represent fluctuations of three rainfall-band patterns in summers in China for the period from 1951 to 2005, and the variation features of these indices are analyzed on both of interdecadal and interannual scales. A new method is proposed to establish an integrative estimation model based on the analysis of rainfall-band indices, and the model is applied to air, ocean factors to estimate their roles on variations of three rainfall-band patterns on different time-scales. The tests of estimation effects show that the fluctuations of three rainfall-band patterns are composed of variations on both significant inter-decadal and interannual scales, of which the interannual variation is mainly influenced by the Elnino/Lanina events, the East Asia monsoon and the ridge locations of subtropical high pressures in western pacific, while the interdecadal variation is mainly controlled by the Pacific decadal oscillation and interdecadal oscillations of the Arctic oscillation, ENSO, Nino3 sea surface temperature and summer monsoon. The estimated results from the integrative estimation model of rainfall-band patterns suggest that the way of estimation first according to each time scale of both the interdecadal and interannual scales, then estimating with an integration, which is proposed in this paper, has an obvious improvement on that without separation of time scales.  相似文献   

13.
The relationship between the inter-annual variations of the earth rotation, atmospheric angular momentum (AAM), sunspot number and El Niño is analyzed. The result shows that the inter-annual variation of the earth rotation responds to the variation of AAM and the pregnancy of El Niño timely. Generally, the inter-annual component of the earth rotation will reach zero in a changing process that increases from the negative to the positive extreme before El Niño occurs about half year or more. And the solar activity may have certain influence on the appearance of El Niño. We consider that El Niño will possibly appear around the end of 2001.  相似文献   

14.
Three variation indices are defined to objectively and quantitatively represent fluctuations of three rainfall-band patterns in summers in China for the period from 1951 to 2005, and the variation features of these indices are analyzed on both of interdecadal and interannual scales. A new method is proposed to establish an integrative estimation model based on the analysis of rainfall-band indices, and the model is applied to air, ocean factors to estimate their roles on variations of three rainfall-band patterns on different time-scales. The tests of estimation effects show that the fluctuations of three rainfall-band patterns are composed of variations on both significant inter-decadal and interannual scales, of which the interannual variation is mainly influenced by the Elnino/Lanina events, the East Asia monsoon and the ridge locations of subtropical high pressures in western pacific, while the interdecadal variation is mainly controlled by the Pacific decadal oscillation and interdecadal oscillations of the Arctic oscillation, ENSO, Nino3 sea surface temperature and summer monsoon. The estimated results from the integrative estimation model of rainfall-band patterns suggest that the way of estimation first according to each time scale of both the interdecadal and interannual scales, then estimating with an integration, which is proposed in this paper, has an obvious improvement on that without separation of time scales.  相似文献   

15.
Interdecadal variability in the tropical Indian Ocean has been analyzed based on the long-term climatic observational data. Case study showed that strong interannual signals formed at the surface can penetrate the depth of seasonal thermocline, where the anomalies last a couple of years. Artificial time series based on damping with exponential decay of selected strong events agree well with the detected interdecadal variability in the tropical Indian Ocean. A possible dynamic explanation for interdecadal variability in the tropical Indian Ocean was proposed that irregular interannual signals can lead to a slowly evolving climatic background with the interdecadal time scale through damping of the memory about anomalies in the seasonal thermocline.  相似文献   

16.
A series of very successful Continuous Very Long Baseline Interferometry Campaigns (CONT) have been carried out at irregular intervals since 1994. One of the goals is to support high-resolution earth rotation studies. The most recent CONT08 campaign was conducted with a network of 11 observatories at an increased recording rate of 512 Mbit per second over a fortnightly time span, from which stronger diurnal variations of the Earth Rotation Parameters (ERP) have been detected. We compared the high-frequency ERP from VLBI and GPS observations during CONT02, CONT05 and CONT08 with the atmospheric angular momentum functions derived from the National Centers for Environmental Prediction/National Center for Atmospheric (NCEP/NCAR) during these periods. We attribute the detected diurnal discrepancies between the theoretical models and the CONT08 observations to atmospheric excitations.  相似文献   

17.
将地球的潮汐力分解为两个分力 FC1,FC2 ,在黄道坐标系内分别讨论其连续性特征 ,针对各分力振幅的连续性俯视特征 ,映射出各潮汐分力的全球性特征分布 ,进而讨论了各个特征曲线交点的属性 ;在直角坐标系内研究了海潮等振幅曲线的表示方法 ,论述了潮汐振幅极大点在地球公转过程中的位置变化 ,及在自转过程中的时间、地点变化特点 .最后指出 :1由潮汐分力导致潮汐波的振幅具有对称性 ;2潮汐等振幅线为环形线 ;3海潮极大点的绝对振幅主要受所在海域的海水质量控制 ;4大气、地幔潮汐振幅的连续性特点与海潮具有相似性 .  相似文献   

18.
The prediction of rainfall in the Yangtze River valley, especially, during flood seasons is the main means for scientists in China working on and the understanding of rainfall-associated processes is a crucial component of this effort. It can be derived f…  相似文献   

19.
以小行星有可能碰撞地球为依据,分别在地球作近似定轴转动和定点转动的两种情况下,讨论了在碰撞的时候地球自转运动可能发生的变化.文章建立了与此相应的Euler方程,得到了该方程的解析解.由这些公式文章说明了SL9彗星的撞击,对木星的自转速率是没有影响的.基于Chicxulub陨石坑的一个模拟碰撞的数值计算中,文章获得结论:小行星对地球的大型碰撞有可能影响地球的自转运动.  相似文献   

20.
The deep reason of severe disaster weather with the relationship among the earth nutation, rotation and atmos- pheric change is explored based on the effective results about the disaster weather prediction of the long term made by the variation of the earth rotation in near 10 years. It is discussed the relationship between the subtropical anticyclone and subtropical easterlies to aim at the problem of high temperature and drought in the globe, further more, the comparison analysis has been made to the earth nutation and the variation of rotation. The research results show that the reasons of severe disaster weather not only are due to atmosphere itself, but have some variation information of earth movement which could be used for the weather forecast.  相似文献   

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